CVE-2026-23240
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: tls: Fix race condition in tls_sw_cancel_work_tx() This issue was discovered during a code audit. After cancel_delayed_work_sync() is called from tls_sk_proto_close(), tx_work_handler() can still be scheduled from paths such as the Delayed ACK handler or ksoftirqd. As a result, the tx_work_handler() worker may dereference a freed TLS object. The following is a simple race scenario: cpu0 cpu1 tls_sk_proto_close() tls_sw_cancel_work_tx() tls_write_space() tls_sw_write_space() if (!test_and_set_bit(BIT_TX_SCHEDULED, &tx_ctx->tx_bitmask)) set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask); cancel_delayed_work_sync(&ctx->tx_work.work); schedule_delayed_work(&tx_ctx->tx_work.work, 0); To prevent this race condition, cancel_delayed_work_sync() is replaced with disable_delayed_work_sync().
Severity
CRITICAL
CVSS score
9.8
(v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-03-10 18:18:13.533000
Last modified
2026-10-19 19:17:43.143000
View original CVE JSON
{
"id": "CVE-2026-23240",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-03-10T18:18:13.533",
"lastModified": "2026-10-19T19:17:43.143",
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{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntls: Fix race condition in tls_sw_cancel_work_tx()\n\nThis issue was discovered during a code audit.\n\nAfter cancel_delayed_work_sync() is called from tls_sk_proto_close(),\ntx_work_handler() can still be scheduled from paths such as the\nDelayed ACK handler or ksoftirqd.\nAs a result, the tx_work_handler() worker may dereference a freed\nTLS object.\n\nThe following is a simple race scenario:\n\n cpu0 cpu1\n\ntls_sk_proto_close()\n tls_sw_cancel_work_tx()\n tls_write_space()\n tls_sw_write_space()\n if (!test_and_set_bit(BIT_TX_SCHEDULED, &tx_ctx->tx_bitmask))\n set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask);\n cancel_delayed_work_sync(&ctx->tx_work.work);\n schedule_delayed_work(&tx_ctx->tx_work.work, 0);\n\nTo prevent this race condition, cancel_delayed_work_sync() is\nreplaced with disable_delayed_work_sync()."
},
{
"lang": "es",
"value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\ntls: Corrección de condición de carrera en tls_sw_cancel_work_tx()\n\nEste problema fue descubierto durante una auditoría de código.\n\nDespués de que se llama a cancel_delayed_work_sync() desde tls_sk_proto_close(), tx_work_handler() aún puede ser programado desde rutas como el gestor de ACK Retrasado o ksoftirqd. Como resultado, el trabajador tx_work_handler() puede desreferenciar un objeto TLS liberado.\n\nEl siguiente es un escenario de condición de carrera simple:\n\n cpu0 cpu1\n\ntls_sk_proto_close()\n tls_sw_cancel_work_tx()\n tls_write_space()\n tls_sw_write_space()\n if (!test_and_set_bit(BIT_TX_SCHEDULED, &tx_ctx->tx_bitmask))\n set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask);\n cancel_delayed_work_sync(&ctx->tx_work.work);\n schedule_delayed_work(&tx_ctx->tx_work.work, 0);\n\nPara prevenir esta condición de carrera, cancel_delayed_work_sync() es reemplazado por disable_delayed_work_sync()."
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